This is the 9160th most frequent Russian word.
серафима
"Серафима" is a feminine given name derived from "серфим," meaning "seraph," referring to a celestial being or angel in Christian theology.
In this sentence, 'Серафима' is used as a proper noun referring to a person's name.
Серафима красива и талантлива.
Serafima is beautiful and talented.
Here, 'Серафиме' is the dative case of 'Серафима', showing that the action is directed towards her.
Я написал письмо Серафиме.
I wrote a letter to Serafima.
In this sentence, 'Серафимой' is the instrumental case of 'Серафима', indicating the involvement of Serafima in the action.